Hands On! SRAM XX1 1×11 Group – Details, Pics & More!

SRAM XX1 1x11 11-speed mountain bike crankset

We paid a little visit to SRAM’s World HQ in Chicago to get a close up look at the new XX1 11-speed mountain bike group, and here are the pics. Plus, we have some updated info on how the cassette mounts, and how they crammed an extra cog on there without making an ultra-narrow chain.

UPDATED: Pic of the Driver Body added at bottom.

The new single-ring XX1 crankset is a simple thing of beauty. Sure, only having to deal with one ring opens a few doors to play with the way the ring mounts, but hopefully the design foreshadows future XX groups. The spider curves and angles, looking very similar to Red, but it’s the backside that’s the real looker…

SRAM XX1 1x11 11-speed mountain bike crankset

Bolts thread directly into the chainring, just like XX. The spider is shaped to push the chainring in the right rotation as you pedal, taking a bit of the stress off the bolts. On the forward facing edge, though, it’s open, making ring swaps quick and easy. Just unbolt it, rotate the ring forward and pull it over the spider and crankarm. Reverse the process and you’re rolling again with, pardon the brand speak, just the right gear.

SRAM XX1 1x11 11-speed mountain bike crankset

The alternating thin and thick teeth keep the chain in place with minimal lateral movement. It peeled off as easy as ever, but there was only enough side-to-side wiggle to accommodate movement across the cassette’s range. It really does seem like it should negate the need for a chainguide.

SRAM XX1 1x11 11-speed mountain bike crankset

The XX1 crankset uses a 76mm BCD in case you’re wondering.

SRAM XX1 1x11 11-speed mountain bike trigger chain

The chain looked pretty much the same as their standard chains if slightly chunkier in appearance. It certainly didn’t seem any more narrow.

SRAM XX1 1x11 11-speed mountain bike trigger shifter

Likewise, the XX1 trigger shifter looks more or less the same as the XX one save for graphics. And there’s no front shifter.

SRAM XX1 1x11 11-speed mountain bike trigger shifter

Grip Shift will also be offered, but it, along with the rear derailleur weren’t on hand for inspection. All of these are officially prototype “non rideable samples” that supposedly varied a bit from final production, but in ways you won’t notice by looking at them. In other words, we couldn’t weigh them because they may not be representative of the final product. Since the U.S. development team was tied up with the new Red when this project started, the entire XX1 project was run in their German offices. The U.S. group still handles graphics for it, but at the moment, what you see here is the sum total of XX1 parts they have in the U.S.

SRAM XX1 1x11 11-speed mountain bike trigger cassette

The XX1 cassette takes their one-piece machining to new levels. Other than the back plate, all cogs are machined from a single piece of steel.

SRAM XX1 1x11 11-speed mountain bike trigger cassette

Even the smallest 10T cog is part of the whole!

SRAM XX1 1x11 11-speed mountain bike trigger cassette

In order to get 11 normally spaced cogs to fit on a hub, SRAM got creative in several ways. First, they redesigned the freehub body. Called the Driver Body (sadly, they didn’t have an example of this on hand either), it’s a stepped design that gets smaller under the smaller cogs.

The inner “tube” part of the cassette is now the lock ring. Or, more accurately, the cassette itself is the lock ring. The grooves on the very back section slide onto the Driver Body much the same way a typical cassette slides onto a freehub body, except there’s no single small groove that forces the cassette into one place. The threads directly behind those grooves are what thread the cassette onto the Driver Body. The front of the cassette is grooved to accept a standard lockring tool, which is how you tighten it onto the hub.

By eliminating the lock ring, they gained about 1.5mm on the outside edge. According to our tech rundown with DT Swiss, their 11-speed hubs allowed an extra 1.8mm of freehub width. That puts the total at about 3.3mm, not quite enough to add another cog, so…

SRAM XX1 1x11 11-speed mountain bike trigger cassette

…SRAM dished the 42T cog (which serves as the backplate) to follow the contour of the spoke angle a bit and take advantage of otherwise wasted space. Brilliant.

SRAM XX1 1x11 11-speed mountain bike trigger cassette

Each cassette takes 90 minutes or so to machine. Here’s what the original Red cassette looks like through the stages:

SRAM Red road bike cassette machined from solid block of steel

The new Red and the XX/XX1 cassettes get additional machining between the cogs to help clear debris and save more weight.

SRAM XX1 1x11 11-speed mountain bike trigger cassette

Until you see it in person, it’s hard to visualize just how big a 42T cassette is. It’s big.

SRAM XX1 1x11 11-speed mountain bike trigger cassette

SRAM XX1 1x11 speed mountain bike driver body freehub closeup

SRAM’s MTB drivetrain product manager snapped this photo for us. It’s the  Driver Body’s main assembly, but there’s a smaller part that extends beyond the bearing that’s visible here. This is from a DT hub, not a SRAM one, and possibly pre-production since it does have the one smaller flange at the back end.

Comments

PDXFixed.com - 07/07/12 - 3:04pm

Why not go with a spiderless chainring? The ability to swap chainrings easily is irrelevant since the chain length has to be very precise to control the angle of the X-Horizon rear derailleur. If you swap chainring sizes, you are effectively adding or removing links from the chain, causing the alignment of the upper jockey wheel to be thrown off.

Todd - 07/07/12 - 5:38pm

“Like it should negate the need for a chainguide”, I really hope you put that to the test and report back. Right now, hate it, but gotta have it. Would be so clean without it.

Igor - 07/07/12 - 6:33pm

Because then you would not be able to change chain rings in different sizes. Also the distance is relative to the bike so you already have to shorten the chain. It will never be optimal if it’s not made for only specific bike or predetermined length. The design still make sense to me. Awesome stuff!

a - 07/07/12 - 7:39pm

Crank may use a 76mm BCD… but it looks like the arms aren’t evenly spaced at 90 degree angles so dont try making one! About 10.5 teeth behind the crank arm and 9 on the opposite side with just over 8 top and bottom?…

Bob - 07/07/12 - 10:24pm

@PDXFixed
As long as your chainring has an even number of teeth, and your chain has an even number of links, they’ll always mesh properly.

Gordo - 07/08/12 - 1:42am

Ritchey was dishing the inside cog a long time ago with their first 2×9 set ups.

carl - 07/08/12 - 2:16pm

Sooooo…… you need a dedicated hub to mount this monster? As in a new wheel? Sweet…. I didn’t know what to do with all my extra $$$$!

RUSTYDOGG - 07/08/12 - 7:42pm

Why does this exist?

someslowguy - 07/08/12 - 10:24pm

PDXFixed.com – if you have a spiderless chainring then you can’t have an SRM or Quarq. Just saying.

Hmmm - 07/09/12 - 7:23pm

90 mins to machine a cluster, from a block of steel. What a waste of energy and material. Not a very ‘green’ way to to go about business….. This ‘weight’ obsession cycling has, is getting on my nerves.

DiHydro - 07/10/12 - 5:48pm

@Hmmm, as opposed to what manufacturing method, stamping? If they didn’t make the cassette out of one piece of steel it would be machined out of more smaller pieces of steel causing even more waste! Then you have to order or make fasteners to hold the cogs together, requiring more trucks to come into the factory every day, and as you should know, trucks certainly aren’t the greenest thing around, are they?

Krank - 07/16/12 - 11:00am

Why not just take one of the chainrings off a XX crankset and have basically the same thing? Unless you’re a huge baby who somehow needs a 42t cassette cog.

paulbalegend - 07/26/12 - 12:50am

@DiHydro and @DiHydro: what the hell are you pendejos talking about? No metal is wasted — regardless of the process. At virtually any company operating CNC machines, all the scrap is melted down and reused!

RUSTYDOGG: It exists because more than 1 ring is not currently necessary for any serious rider, but people are hesitant to believe that fact because they’re afraid of the range being too small. (In fact, it’s not too small, 11-36 cassettes have been around for a while and along with a single ring offer plenty of range for most riders, hence the reason half of pro teams are using 1x setups these days. Indeed i have plenty of range with my 9-speed 11-34 cassette on a single 32T ring.) So to convince the skeptics, SRAM made a rig with all the range of a double or triple (420%) but only the one ring.
There are many advantages of 1x, including generally saving over a full pound, gaining bottom bracket clearance for getting over logs, simplicity of shifting, faster shifting, tighter cable tension, less chain derailments caused by bumps, cheaper, less likely to break, etc.
Eventually people will realize 1x kicks ass, that 3/4 of the ratios in their old setup overlapped and were worse than useless, and that there’s actually no need for the monstrous 42T cog or the low-efficiency 10T cog.

paulbalegend - 07/27/12 - 11:37am

@Hmmm and @DiHydro: what the hell are you pendejos talking about? No metal is wasted — regardless of the process. At virtually any company operating CNC machines, all the scrap is melted down and reused!

@RUSTYDOGG: It exists because more than 1 ring is not currently necessary for any serious rider, but people are hesitant to believe that fact because they’re afraid of the range being too small. (In fact, it’s not too small, 11-36 cassettes have been around for a while and along with a single ring offer plenty of range for most riders, hence the reason half of pro teams are using 1x setups these days. Indeed i have plenty of range with my 9-speed 11-34 cassette on a single 32T ring.) So to convince the skeptics, SRAM made a rig with all the range of a double or triple (420%) but only the one ring.
There are many advantages of 1x, including generally saving over a full pound, gaining bottom bracket clearance for getting over logs, simplicity of shifting, faster shifting, tighter cable tension, less chain derailments caused by bumps, cheaper, less likely to break, etc.
Eventually people will realize 1x kicks ass, that 3/4 of the ratios in their old setup overlapped and were worse than useless, and that there’s actually no need for the monstrous 42T cog or the low-efficiency 10T cog.

Mike - 07/30/12 - 7:21pm

About the chainrings…can normal rings be used? I understand chain retention may suffer.

If normal rings will not fit between the XX1 links, would forming a ring from a cog work?

With a 28T chainring the upper gears would be a waste for me, and a lower low could prove useful.

By turning a cog into a chainring, could one then run wheelsets with different cog sets, say a 10 speed
and one with a 11 speed cog set by using the XX1 shifter?

Jon - 07/31/12 - 11:03am

I am stoked about this! I run an X9 1×9 setup right now with a 32t chainring and an 11×34 cassette. I love the simplicity and lightness of it, and it is amazing for about 95% of all the trails that I have ridden. The only times I have suffered are trying to keep up with friends on very smooth, super fast downhill runs (guessing about 40mph), and super long, super steep, technical climbs. I don’t have quite enough gearing to start off again once I lose momentum on an obstacle, when I can’t carry momentum up the hill. I was bummed that I might have to switch to a 2×10 setup on my next bike, but this will be perfect!

@RUSTDOGG: Try just staying in your middle chainring next time you go ride a trail, and see how much of it you can ride, and how much nicer it is to not be switching between 2 shifters the whole ride, trying to find the right ratio. If you need a lower one, just shift down, if you need a higher one, just shift up. Plus you can lose over a pound of weight.

@Krank: I agree that a 42t cassette would be overkill with my current 32t chainring, but the thing I am excited about is being able to run a larger 34t or 36t front chainring, still have a lower gear than I currently have, and be able to haul ass on downhills or paved transfer sections between trails, where I am usually spinning pretty fast in my highest gear right now.

paulbalegend - 08/10/12 - 3:59pm

right on, Jon.

stumpjumper evo 29er - 08/28/12 - 4:40pm

I run a 1×10 set up on my stumpy . You cannot beat it for its simplicity and quietness. Only on long steep or rough climbs do you need a little exta tourque. 1×9,1×10 and now 1×11 is the way to go.

Haywood - 11/30/12 - 1:41pm

So this takes 90 minutes to machine compared to the 9 hours they said the XX cassette took to machine? Can ya pass the savings onto the customer?

Cebu Triathlon - 12/18/12 - 11:52pm

Wow! 11 speed and 1 crank. that is sick,and great weight being saved too.

Shawn - 01/10/13 - 5:14pm

I started running a 1×9 years ago and have never looked back. It’s simple design, thoughtless shifting, less weight, cleaner look, less expense, better clearance, etc…only thing that bums me out is the fact that more people will be using it and my bike won’t look so unique anymore :-)
Nice job SRAM but lets hurry up and get it commercially available before race season. I’ve got a frameset that needs a new xx1 drivetrain. At 5’4″ and short legs, how about 165mm crank arms?

Wayne - 01/30/14 - 6:25pm

Any reason they went with a 76BCD? Their x2 setup is 80bcd, why the change?

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